The present invention relates to an emergency unlocking device at shaft doors of elevators, wherein a rotatably mounted locking lever movable with the shaft door and acting on an emergency actuating element is provided.
The shaft doors of the elevator are, in the locked state, locked with the door frame, wherein usually a locking lever rotatably mounted at the shaft door is in engagement with a locking element fastened to the door frame. In order to gain access to the elevator shaft in the case of breakdowns or in other emergency cases it must be possible for an authorized person to open a locked shaft door from the floor, for which purpose emergency unlocking devices are provided.
A device for emergency unlocking of elevator doors is shown in the European Patent Application EP-A-838425, in which a hook lock rotatably mounted at a carrier plate connected with the suspension carriage of the shaft door is provided. The hook lock is formed as a double lever, wherein one lever arm has a hook and the other lever arm is provided with a weight so that the hook is always biased upwardly. The hook in that case engages in a recess of a fixedly mounted anchoring element so that a lateral displacement of the suspension carriage or the shaft door is not possible. A release web with a bent-over portion, which is pushed under a release rod on closing of the shaft door, is fastened to the hook lock. The release rod is fastened to a rotatably arranged rotary lever that is held in the locked setting by means of a tension spring. A Bowden pull is connected by one end with the rotary lever, wherein the other end of the Bowden pull is fastened to a pull lever of an actuating element. The actuating element is arranged at the underside of a visible door frame member and is accessible from the floor of the building.